Janka Hardness Scale for Wood Flooring
In this article 6 sections
The Janka hardness scale compares how strongly different woods resist a standardized dent. It is useful when two flooring species are otherwise a close match, but it is not an overall durability score.
A harder wood generally takes more force to indent. That does not tell us how easily the finish will scratch, how much the boards will move with moisture, or how well a particular flooring product was made.
What a Janka rating actually measures
The side-hardness test measures the force needed to press a steel ball 0.444 inch in diameter halfway into a wood sample. In the United States, the result is normally shown in pounds-force, or lbf. A rating of 1,290 means the test required 1,290 pounds-force under the stated test conditions.
It helps compare dents
A higher number means the sample resisted the standardized indentation more strongly.
It does not rate the finish
Scratches and surface wear involve the finish, grit, furniture, pet claws, maintenance, and how visible marks are on that color and sheen.
It does not rate the whole floor
Milling, grade, construction, moisture response, installation, and individual boards still affect performance.
Janka hardness chart for common flooring woods
Northern red oak at 1,290 lbf is a useful benchmark. White oak is slightly harder, while hard maple and several hickories sit higher. Black walnut and black cherry sit lower, yet both can still make long-lasting residential floors when their appearance and expected wear fit the room.
The values below are USDA side-hardness figures for clear wood, generally tested or adjusted near 12% moisture content. They are species comparisons, not minimum ratings for every flooring board or finished product.
| Wood species | Janka hardness (lbf) |
|---|---|
| Ipe | 3,680 |
| Brazilian cherry (jatoba or courbaril) | 2,350 |
| Sucupira | 2,140 |
| Jarrah | 1,910 |
| Shagbark hickory | 1,880 |
| Purpleheart | 1,860 |
| Pecan hickory | 1,820 |
| Kempas | 1,710 |
| Black locust | 1,700 |
| Sapele | 1,510 |
| Hard maple (sugar maple) | 1,450 |
| White oak | 1,360 |
| White ash | 1,320 |
| American beech | 1,300 |
| Northern red oak | 1,290 |
| Yellow birch | 1,260 |
| Southern red oak | 1,060 |
| Black walnut | 1,010 |
| Teak | 1,000 |
| Black cherry | 950 |
| African mahogany | 830 |
| Coast Douglas-fir | 710 |
| Yellow-poplar | 540 |
| Eastern white pine | 380 |
Source note: Values are from the USDA Forest Products Laboratory’s Wood Handbook, Chapter 5. The imported-wood values were compiled from world literature, and the USDA notes that an individual sample may not represent an entire species. Figures are best used for relative comparison.
Why Janka hardness charts sometimes disagree
The test itself is straightforward. The label attached to a number is not always as simple.
- One common name may cover several species. Hickory is a good example. The USDA lists different values for pecan, shagbark, pignut, and other hickories.
- Moisture content affects hardness. Green wood and dry wood from the same species do not produce the same result.
- Trade names can be loose. Acacia, eucalyptus, mahogany, and similar labels may describe more than one species or product.
- Manufactured materials depend on the product. Bamboo is a grass, and strand-woven, horizontal, vertical, and carbonized bamboo can have very different published ratings. The manufacturer and test method matter more than a generic bamboo number.
- Wood varies naturally. Published values are averages or representative test results, not a guarantee for every board.
This is also why a supplier’s current technical sheet is more useful than a generic chart when an exact product is being compared.
Harder does not automatically mean better flooring
A high Janka number can be helpful where dent resistance is a priority. It can also come with tradeoffs. Very dense wood may be more demanding to cut, nail, sand, or repair, and hardness says nothing about whether the grain, color, sourcing, or movement characteristics fit the project.
The finish and the wood handle different kinds of wear. Janka hardness describes resistance to an indentation in the wood sample. The finish is the first surface exposed to grit, sliding furniture, pet claws, and cleaning. A very hard species can still show scratches, and a lower-rated species is not automatically unsuitable.
Hardness and dimensional stability are also separate properties. A hard wood can still expand and shrink as its moisture content changes. Our wood flooring movement chart explains that comparison separately.
Solid and engineered flooring use the number differently
For solid flooring, the species value is a useful general comparison because the board is the same wood through its thickness. The actual floor still varies by grade, grain, moisture, milling, and finish.
For engineered flooring, a published species rating describes the wood used for the wear layer, not the complete plank. Wear-layer thickness, core construction, factory finish, milling, and manufacturer requirements remain part of the product decision. See our comparison of solid and engineered hardwood flooring for the broader differences.
The useful way to use the Janka scale
Start with the woods that produce the color and grain wanted for the room. Then use Janka hardness to understand the relative dent resistance within that realistic group.
If two choices are close on the chart, the number is rarely the deciding factor. The actual flooring product, finish, board construction, milling, expected indoor conditions, and willingness to accept normal dents and scratches usually tell us more about how the floor will live.
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